Dry cell and process of assembling the same



@.VHAMBUECHEN- DRY CELL AND PROCESS 'OFASSEWIBLING THE SAME.

APPLICATION FILED MAH-4 *IZ-9v, I922.

Patated Deo. 5, 1922 LASS l@ III :Illllllnlf ll/III!II/IIIIIIJIIIIAIIIII :IIIIII Patented Dec. 5, 1922.

srEs PATENT OFFICE.

CARL I'IIAIVIBUECHEN, OF NEW YORK. N. Y., ASSIGNOR T0 UNION CARBIDE & CARBON RESEARCH LABORATORIES, INC.,

A CORPORATION OF NEW YORK.

:DRY CELL AND PROCESS OF vASSEMBLING' THE SAME.

Application filed March 29, 1922.

Be it known that l. (fam, Hanni'ixfHrzN, a citizen of the llnited States. residingat New York. in the county 'of Yew York and State of New York. have invented certain new and useful Improvements in Dry Cells and lrocesses of Assembling the Same, of which the I' its capacity. That portion of the material followingr is a specification.

This invention relates to dry cells and has particular reference to improvements in the formation of a protective layer adherent to the inner surface of zinc container electrodes, and to the assembly of depolarizing bobbins and electrolyte paste with electrodes thus protected.

The method as above broadly outlinedis disclosed in UnitedStates Patents 1,295,475,

' dated Fb. 25, 1919, and 1,375,202, dated i April 19, 1921, both granted to H. F. French and R. C. Benner. According to these patents a film or layer of paste is applied to substantially the'entire inner surface of zinc cups and is gelatinized thereon by suitable Y application of heat. In this manner the electrode is provided with a tough, tenacious coating. The procedure described makes. 1t

possible to use bobbins without the sustain'- ing fabric wrapping which 1s .ordlnarily required to prevent detached particles of depolarizer from reaching the Zinc and there forming centers for destructive local act1on,

The elimination of the wrapping results in 1 an improvement in the service characterlstics of the cell and in a large decrease in the cost of production.

According to my invention, the above procedure has been modified in certain advantageous respects. Among the distinguishing features of the present process are the provision of an initial cooked paste layer on the lower part only of the container electrode,

/ and the distribution of pastev within the cell by displacement upon the insertion of the i bobbin. rlhe invention will be described in detail in connection vwith the accompanying` drawings, illustrative of the several steps in the preparation of cells having no fabric or 4paper spacing the bobbin from the zinc, and commonly known as non-lining cells. In these drawings,

Fig. l is a vertical central section through a zinc cup containing paste.

Fig. 2- is a similar View, showing a paste layer adherent to the cup, 'l

Serial No. 547,800.

Fig. '-is a vertical section through the cell .af-ter the bobbin has been introduced, and

Fig. 4 is a view similar to Fig. @-5. showing the cellafter the lfinal heating operation.

In the improved method. a metal cup. dcnoted by reference numeral 2. is charged with gelatinizable material 3 to about one-third of contiguous to the cup 'is then gelatinized to form aprotective layer 4. The material 3 will ordinarily heya cerealpaste containing electrolyte-salts, and in such case may he rapidly gelatinized by immersing the cup in hot water. An immersion of 2O to el() seconds duration in Water at a temperature of about 70? C. forms a tough layer of cooked paste adherent to the metal.

A mix bobbin 5, preferably without a wrapping', is now inserted in the cup The bobbin-may rest upon a gelatinized layer at the base of the cup, or upon an insulating disk. The insertion of the bobbin causes displacement of the ungelatinized central body of paste upwardly to till the annular space between 'the bobbin and the upper portion of the cup. The bottom of the bobbin is ccntered in the cup by the circumferential gelatinized layer 4. The quantity of paste may be so adjusted as to fill the c up to the top of the bobbin, or, if necessary, the paste level may be adjusted to secure this result. The cup: is then heated to gelatinize the paste about the upper part of the bobbin. This heating may continue for about two minutes. It will be understood that the method and duration of heating referred to above ma be varied to suit particular conditions. The upper part of the bobbin may be centered manually or by suitable mechanical means, and the cell maybe provided with a seal and otherwise completed in tne usual manner.

An essential feature of my invention, independent of any particular method, is the 'formation ofl a spacing. and protective coating upon the lower interior surface of a metal container electrode, and any suitable procedure may be adopted for forming such a coating. I have found that it is -unnecessary initially to gelatinize a layer of paste upon the entire vinterior surface of the electrode, as proposed in thepatcnts mentioned herein, and the present procedure is simplified by the omission of the steps of pouring out they ungelatinized paste and ics ' again intrmlucing it after the insertion ot the hobhin. Also, itis unnecessary to provide means lor preventing adherence of paste to that portion of the cup with which the sealingl material should make contact. The present procedure iswell adapted to be arried out by machines, an important advantage in large-scale manufacture. These and various other distinctive features and advantages ot' the present invention will be apparent from the foregoing description, and are included within the scope ot' the claims appended hereto. I

I claim:

l. Process ot' preparinghollow electrodes for dry cells7 comprising applying a protective coating' to `a portion only oi the interior surface ot' such electrodes,

2. Process of preparing` hollow electrodes for dr7 cells com risinfr oelatinizino a..

.l a e, a es layer of paste upon a portion only of the interior surface of such electrodes` Process of preparing container electrodes for dry cells of the non-lining,r type, comprisinlg` gelatinizing a `layer of paste upon approximately the lower third oi the inner surface of such electrodes.

4t. Process of preparing dry cells ot the non-lining type, comprising placing gelatinizable material in the lower portion or" a metal container, gelatinizing the circumferential portion of the material and insertinga mix bobbin into the container, Where- `by the ungelatinized material is displaced upwardly between .the container and tlie bobbin.

5. Process of 'preparing dry cells of the non-lining type, comprising placing new electrolyte paste in the lower portion of, a4

zinc container electrode, immersing the containcr' in hot water to gelatinize the paste contiguous to the container, and inserting a mix hobbin into the container, whereb the ungelatinized paste is displaced upwar ly between the container and the bobbin.

t5. Process ot' preparing dry cells ofthe non-lining type comprising placingraw electrolyte paste in the-lower` portion of a zinc containcl-'electrode7 immersing the con.- tainer in hot water to gelatinize the paste contiguous to the container, and gelatiniz CARL HAMBUECHEN. 

